Italy's premier is leading calls for EU action, including a summit, on the increasing number of migrant deaths in the Mediterranean. EU foreign ministers are meeting to discuss the issue.

Following the latest sinking of a migrants' boat off the coast of Libya at the weekend, Italian Prime Minister Matteo Renzi has called for EU action on the issue.

EU foreign ministers are meeting in Luxembourg on Monday morning to discuss the crisis. They will also discuss the situation in war-torn Libya where up to 90 percent of the migrants begin their dangerous sea-journey to Europe.

Up to 700 people are feared drowned after their 20 meter (70ft) fishing boat sank late on Saturday night. Only 28 migrants were rescued. The coffins with the bodies of victims have been taken to Malta.

The United Nations' Refugee Agency (UNHCR) in Italy said there had been a thirty-fold increase in the number of migrants drowning in the Mediterranean since the start of the year compared with the same period for 2014.

Renzi said that Libya was the key problem in originating the dangerous voyages for migrants across the Mediterranean. He said more needed to be done to stop boats organized by traffickers from leaving. He called it "the slavery of the 21st Century", and added: "It is unthinkable that in the face of such a tragedy, there isn't the feeling of solidarity which Europe has shown in other instances."

EU under fire

The EU has been criticized for its inaction since the nine-million-euro ($9.7 million) Mare Nostrum rescue operation was ended last October. Italy had failed to persuade European partners to help meet operating costs. Some EU members expressed fears that the operation was encouraging smugglers and migrants to organize more trips across the sea.

Mare Nostrum was replaced by a much smaller EU-run border protection program, named Triton, which operates only within 50 kilometers (30 miles) of the Italian coast.

Head of the International Organization for Migration (IOM) William Lacy Swing called for the Mare Nostrum operation to be restored: "Mare Nostrum saved 200,000 lives between October 2013 and December 2014," he said on Monday. "Get Mare Nostrum back out there, give it the support it needs to save these lives."

Swing said the Triton operation was "not adequate."

"They don't have a mandate, they're a border protection agency, not a life-saving agency," Swing said.

Italian Federica Mogherini, the EU foreign policy chief, has added a discussion of the crisis to the agenda of a foreign ministers' meeting in Luxembourg on Monday.